Method and computer program product for controlling the control effectors of an aerodynamic vehicle

ABSTRACT

A method and computer program product are provided for controlling the control effectors of an aerodynamic vehicle including, for example, the respective positions of nozzles and aerodynamic surfaces, to affect a desired change in the time rate of change of the system state vector. The method initially determines differences between anticipated changes in the states of the aerodynamic vehicle based upon the current state of each control effector, and desired state changes. These differences may be weighted based upon a predetermined criteria, such as the importance of the respective states and/or the weight to be attributed to outliers. The differences between the anticipated and desired state changes are converted to the corresponding rates of change of the control effectors. Control signals are then issued to the control effectors to affect the desired change in the time rate of change of the system state vector.

FIELD OF THE INVENTION

[0001] The present invention relates generally to a method ofcontrolling the control effectors of an aerodynamic vehicle and, moreparticularly, to an integrated method for controlling the controleffectors of an aerodynamic vehicle, including the aerodynamic surfaces,thrust variations and nozzle vectoring, in order to efficiently cause adesired change in the time rate of change of the system state vector ofthe aerodynamic vehicle during various stages of flight.

BACKGROUND OF THE INVENTION

[0002] During flight, the control of aerodynamic vehicles, such asaircraft, is principally accomplished via a variety of flight controleffectors. These flight control effectors include aerodynamic controlssuch as the rudder, elevators, ailerons, speed brakes, engine thrustvariations, nozzle vectoring and the like. By altering the variousflight control effectors, the system state vector that defines thecurrent state of the aerodynamic vehicle can be changed. In this regard,the system state vector of an aerodynamic vehicle in flight typicallydefines a plurality of current vehicle states such as the angle ofattack, the angle of side slip, the air speed, the vehicle attitude andthe like.

[0003] Historically, the flight control effectors were directly linkedto various input devices operated by the pilot. For example, flightcontrol effectors have been linked via cabling to the throttle leversand the control column or stick. More recently, the flight controleffectors have been driven by a flight control computer which, in turn,receives inputs from the various input devices operated by the pilot. Byappropriately adjusting the input devices, a pilot may thereforecontrollably alter the time rate of change of the current system statevector of the aerodynamic vehicle.

[0004] Unfortunately, flight control effectors may occasionally fail,thereby adversely affecting the ability of conventional control systemsto maintain the dynamic stability and performance of the aerodynamicvehicle. In order to accommodate failures of one or more of the flightcontrol effectors, control effectors failure detection and flightcontrol reconfiguration systems have been developed. These systemstypically remove the flight control effectors that has been identifiedas inoperable from the control system. These systems are thereforedesigned to detect the failure of one or more flight control effectorsand to alter the control logic associated with one or more of the flightcontrol effectors that remain operable in an attempt to produce thedesired change in the time rate of change of the current system statevector of an aerodynamic vehicle requested by the pilot. These failuredetection and flight control reconfiguration systems are highly complex.As such, the proper operation of these systems is difficult to verify.Moreover, these systems introduce a risk that a flight control effectorthat is actually functioning properly may be falsely identified ashaving failed and thereafter removed from the control system, therebypotentially and unnecessarily rendering the control system lesseffective.

[0005] Additionally, the control effectors of an aerodynamic vehiclegenerally have some limitations on their performance. In this regard,the rate of change accommodated by most control effectors is generallylimited to a range bounded by upper and lower limits. By way of example,for aircraft, such as direct lift aircraft, that permit nozzlevectoring, the actual position which the nozzles may assume is typicallylimited to within upper and lower limits. Unfortunately, conventionalcontrol systems do not accommodate limitations in the range of settingsand rate of change of the control effectors. As such, conventionalcontrol systems may attempt to alter a control effector in a manner thatexceeds its limitations. Since the control effector will be unable tomake the desired change, the control system may correspondingly fail toproduce the desired change in the time rate of change of the systemstate vector of the aircraft.

[0006] In addition to the aerodynamic surfaces commonly utilized tocontrol the flight of an aerodynamic vehicle, aircraft has beendeveloped that can provide additional control by means of thrustvariations and/or thrust or nozzle vectoring. For example, somemulti-engine aircraft permit the plurality of engines to be drivendifferently so as to generate different levels of thrust which, in turn,can serve to assist in the controlled flight of the aircraft. As anotherexample, vectoring nozzles that may be commanded to assume any of arange of positions and bi-directional nozzles that direct the exhaust inone of two directions have been developed. By controllably directing atleast a portion of the engine exhaust in different directions, vectoringnozzles, which shall hereafter also generally include bi-directionalnozzles, can also assist in the controlled flight of the aircraft.

[0007] While various control systems have been developed to control theflight control effectors during flight, these control systems generallydo not integrate the control provided by aerodynamic surfaces duringflight with the control needed in instances in which the aircraft hasno, or a negligible, velocity such that the aerodynamic controlsurfaces, such as the rudder, elevators, ailerons or the like, do notsignificantly contribute, if at all, to the lift and attitude control ofthe aircraft. In this regard, direct lift aircraft have been and arebeing developed. Direct lift aircraft have control effectors, such asvectoring nozzles or bi-directional nozzles, that can direct the engineexhaust in different directions to provide lift and attitude control ofthe aircraft. By appropriately positioning the nozzles, a direct liftaircraft can takeoff and land in a substantially vertical manner. Assuch, during takeoff and landing, the aerodynamic control surfaces donot significantly contribute to the lift and the attitude control of thedirect lift aircraft. Instead, the lift and attitude control areprincipally provided and controlled by any thrust variations provided bythe engines and the vectoring of the associated nozzles.

[0008] In order to control the lift and attitude of an aircraft during avertical takeoff or landing, control systems have been developed tocontrol the engines and the associated nozzles. For example, one controlsystem employs an optimization algorithm, termed an LI optimizationalgorithm. While generally effective, this optimization algorithmsuffers from several deficiencies. In this regard, the optimizationalgorithm is computationally complex, thereby requiring substantialcomputing resources and being difficult and costly to expand or scale toaccommodate more sophisticated control schemes, such as the controlscheme necessary to control vectoring nozzles as opposed to simplerbi-directional nozzles. The computational complexity of the optimizationalgorithm may also cause the solution to be approximated in instances inwhich the optimization algorithm cannot arrive at an exact solutionwithin the time frame required to maintain stability of the aircraft. Inaddition, the optimization algorithm may not converge in all situations.In instances in which the optimization algorithm may not converge, theprior solution, i.e., the solution from a prior iteration of theoptimization algorithm, would continue to be utilized, thereby resultingin a sub-optimal solution.

[0009] As such, it would be desirable to provide an improved controlsystem that effectively integrates the various control effectorsincluding the aerodynamic surfaces and the thrust variations and nozzlevectoring so as comprehensively control the aerodynamic vehicle duringdifferent stages of flight, including for example, the vertical takeoffand landing of a direct lift aircraft during which thrust variations andnozzle vectoring dominate the control scheme as well as in flight duringwhich the aerodynamic surfaces provide a greater measure of control. Inaddition, it would be desirable to develop a method of controlling thecontrol effectors of an aerodynamic vehicle, such as a direct liftaircraft, which provides increased flexibility with respect to theremoval or inclusion of a flight control effector that may have failed.In addition, it would be advantageous to provide a method forcontrolling the control effectors of an aerodynamic vehicle, including adirect lift aircraft, in a manner that recognizes and accommodateslimitations in the settings and rate of change of at least some of thecontrol effectors.

SUMMARY OF THE INVENTION

[0010] An improved method and computer program product are thereforeprovided for controlling the plurality of control effectors of anaerodynamic vehicle in order to efficiently bring about a desired changein the time rate of change of the system state vector of the aerodynamicvehicle. Advantageously, the method and computer program product providean integrated control scheme for controlling thrust variations andnozzle vectoring, as well as various aerodynamic surfaces throughout allphases of flight including takeoff, flight and landing. By integratingthe control of thrust variations and nozzle vectoring with the controlof aerodynamic surfaces, the method and computer program product canalso provide control during vertical takeoff and landing scenarios.

[0011] The method and computer program product of one aspect of thepresent invention permits the control of the control effectors to betailored based upon predetermined criteria, such as the relativeimportance of the respective states of the aerodynamic vehicle and/orthe weighting to be given to any outlier measurements. According toanother aspect, the method and computer program product control theplurality of control effectors while recognizing limitations upon thepermissible changes to at least one control effector, such aslimitations upon the rate of change or the range of positions of atleast one control effector. As such, the method and computer programproduct of the present invention address the shortcomings ofconventional control systems and efficiently command the controleffectors so as to alter the time rate of change of the system statevector of the aerodynamic vehicle in a desired manner.

[0012] The method and computer program product control the controleffectors of an aerodynamic vehicle by initially determining the currentcommanded state of the plurality of control effectors including, forexample, the current commanded position of each nozzle, the currentcommanded level of thrust for each engine and the current commandedposition of at least one aerodynamic surface. The method and computerprogram product then determine the differences between anticipatedchanges in the plurality of states of the aerodynamic vehicle based uponthe current state of each control effector and the current flightconditions, and desired changes in the plurality of states of theaerodynamic vehicle. In order to determine the differences between theanticipated and desired changes in the plurality of state rates of theaerodynamic vehicle, the dot product of a vector representing thecurrent commanded state of each control effector and a matrixrepresenting changes in the plurality of states of the aerodynamicvehicle in response to changes in the control effectors at the currentflight conditions is initially determined. In this regard, the matrixincludes a plurality of terms, each of which represents the anticipatedchange in a respective state rate of the aerodynamic vehicle in responseto the change of a respective control effector at the current flightconditions. By considering the effect of changes in a control effectorat the current flight conditions, the method and computer programproduct can rely upon the control provided by thrust variations andnozzle vectoring more heavily during vertical takeoff and landing andupon the control provided by aerodynamic surfaces more heavily once inflight, thereby providing an integrated and robust control scheme. Inorder to determine the difference between the anticipated and desiredchanges in the plurality of states of the aerodynamic vehicle, thevector difference between the dot product and a vector representing thedesired change in the plurality of states of the aerodynamic vehicle isobtained in one embodiment.

[0013] According to one aspect of the present invention, the differencesbetween the anticipated and desired changes in the plurality of statesof the aerodynamic vehicle are then weighted based upon a predeterminedcriteria. In this regard, the differences may be weighted based upon therelative importance of the respective states of the aerodynamic vehicle,thereby permitting those states which are believed to be of greaterimportance to be assigned a correspondingly greater weight. As a resultof this greater weight, the method and computer program product of thisaspect of the present invention will control the control effectors so asto more quickly alter these states than other states having lowerweights assigned thereto. In addition or in the alternate, thedifferences may be nonlinearly weighted by a predefined penalty basedupon the emphasis to be placed upon outliers, i.e., relatively largedifferences between the anticipated and desired changes in the pluralityof states of the aerodynamic vehicle. A predefined penalty may also beutilized to emphasize the importance of certain relationships, such asmaintaining area match for each engine, with relatively large penaltiesbeing assigned to variations from the desired relationship.

[0014] Based upon the weighted differences between the anticipated anddesired changes in the plurality of states of the aerodynamic vehicle,the method and computer program product may determine a second dotproduct of the weighted vector difference and a transpose of the matrixrepresenting changes in the state rates of the aerodynamic vehicle inresponse to changes in the plurality of control effectors. The seconddot product therefore represents the changes in the control effectorsrequired to affect the desired changes in the plurality of states of theaerodynamic vehicle, given the anticipated changes in the plurality ofstates. As such, the weightings assigned to the respective states of theaerodynamic vehicle will correspondingly effect changes in the desiredstate of the control effectors. By utilizing the transpose of the matrixrepresenting changes in the state rates of the aerodynamic vehicle inresponse to changes in the control effectors, the method and computerprogram product effectively cause the control effectors that will havethe greatest impact upon effecting the desired change to be adjusted toa greater degree than the control effectors that will have less impactupon effecting the desired change, thereby improving the efficiency ofthe control scheme. The second dot product may also be weighted by again matrix, one term of which is associated with each control effectorin order to appropriately weight the relative contributions of thecontrol effectors.

[0015] According to another advantageous aspect of the presentinvention, the method and computer program product may also limit thepermissible changes of at least one of the control effectors. In thisregard, the permissible rate of change of one or more of the controleffectors may be limited. Similarly, the position of one or more of thecontrol effectors may also be limited to within a predefined range. Assuch, the method and computer program product of the present inventioneffectively recognize and accommodate limitations of the controleffectors, thereby preventing any attempts to drive the controleffectors beyond their predefined limitations.

[0016] The method and computer program product then issue controlsignals to the plurality of control effectors so as to implement atleast a portion of the desired change in the time rate of change of thesystem state vector of the aerodynamic vehicle. In those aspects of thepresent invention in which the differences between the anticipated anddesired changes in the plurality of states of the aerodynamic vehicleare weighted, the control signals are at least partially based upon theweighted differences. More particularly, in those embodiments in whichthe second dot product of the weighted vector difference and thetranspose of the matrix representing changes in the system state vectorof the aerodynamic vehicle in response to the changes in the pluralityof control effectors is determined, the control signals are at leastpartially based upon the second dot product. Moreover, the controlsignals may be more directly weighted by the gain matrix. Additionally,in those aspects of the present invention in which the permissiblechanges of at least one of the control effectors is limited, the controlsignals issued to the control effectors are subject to the limitationsin the permissible changes of one or more of the control effectors.Thus, at least a portion of the desired change in the plurality ofstates of the aerodynamic vehicle may be implemented without exceedingthe permissible changes of the control effectors.

[0017] Thus, the method and computer program product of the presentinvention provide an improved technique for efficiently controlling thecontrol effectors of an aerodynamic vehicle in order to effect thedesired change in the time rate of change of the system state vector ofthe aerodynamic vehicle. Advantageously, the method and computer programproduct provide an integrated control scheme for controlling thrustvariations and nozzle vectoring, as well as various aerodynamic surfacesthroughout all phases of flight including takeoff, flight and landing.According to one aspect of the present invention, the control of thecontrol effectors may be influenced by weighting based upon apredetermined criteria, thereby permitting the control system to be moreindividually tailored and efficiently implemented. According to anotheraspect of the present invention, the permissible changes of one or moreof the control effectors may be limited such that the desired change inthe time rate of change of the system state vector of the aerodynamicvehicle may be affected without attempting to exceed the permissiblechanges of at one or more of the control effectors.

BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Having thus described the invention in general terms, referencewill now be made to the accompanying drawings, which are not necessarilydrawn to scale, and wherein:

[0019]FIG. 1 is a block diagram illustrating the operations performed bythe method and computer program product of one embodiment of the presentinvention;

[0020]FIG. 2 is a graph representing the affect attributable to theimposition of different predefined penalties; and

[0021]FIG. 3 is an expanded view of the graph of FIG. 2 illustrating theaffect of the imposition of different predefined penalties.

DETAILED DESCRIPTION OF THE INVENTION

[0022] The present invention now will be described more fullyhereinafter with reference to the accompanying drawings, in whichpreferred embodiments of the invention are shown. This invention may,however, be embodied in many different forms and should not be construedas limited to the embodiments set forth herein; rather, theseembodiments are provided so that this disclosure will be thorough andcomplete, and will fully convey the scope of the invention to thoseskilled in the art. Like numbers refer to like elements throughout.

[0023] A method and a corresponding computer program product areprovided for controlling the plurality of control effectors of anaerodynamic vehicle, such as an aircraft, including, for example, adirect lift aircraft capable of vertical takeoff and landing. As knownto those skilled in the art, aerodynamic vehicles have a wide variety ofcontrol effectors with the type and number of control effectorsdepending upon the type and model of the aerodynamic vehicle. By way ofexample, typical control effectors include aerodynamic surfaces, such asthe rudder, elevators and ailerons. Other control effectors includespeed brakes, engine thrust variations and nozzle vectoring includingthe control of bi-directional nozzles. As will be understood by thoseskilled in the art, nozzle vectoring generally includes the positioningof the main lift nozzle and, in some embodiments, the positioning of thenozzles associated with one or more attitude control effectors.

[0024] As described below, the control method of the present inventionintegrates the control of these various control effectors, including theaerodynamic surfaces, thrust variations and nozzle vectoring, to permitimproved control over all phases of flight. Moreover, the control methodadvantageously utilizes the various types of control effectorsdifferently during different stages of flight based, at least in apart,upon the effect occasioned by changes in the various control effectorsat the current flight conditions. For a direct lift aircraft, forexample, the control effectors that are principally utilized duringvertical takeoff and landing are thrust variations provided by eachengine and the associated nozzle positions, i.e., nozzle vectoring, butdo not include the aerodynamic surfaces since the aerodynamic surfacesprovide very little, if any, control since the aerodynamic vehicle hasno forward velocity. Conversely, during wingborne flight, the controlmethod relies more heavily upon the aerodynamic surfaces and much lessheavily upon thrust variations and nozzle vectoring in order toefficiently control the aerodynamic vehicle.

[0025] As shown in FIG. 1 and described hereinafter, the control methodmay be implemented in the discrete domain utilizing digital signals.Alternatively, the control method may be implemented in the continuousdomain utilizing analog signals if so desired. Regardless of the domainin which the control method is implemented, the control method depictedin FIG. 1 is automated and is generally implemented by means of acomputer, such as a flight control computer or the like. As such, thecontrol method is typically embodied in a computer program product whichdirects the flight control computer to issue appropriate commands to theplurality of control effectors in order to control the aerodynamicvehicle as desired.

[0026] As shown, the current commands S issued to the control effectorsare monitored. The current commands S define the current state to whicheach control effector has been commanded. For example, the commandsassociated with an aerodynamic surface such as a rudder, elevator oraileron define the position to which the respective aerodynamic surfaceis currently being directed to assume. Similarly, commands may be issuedto the respective engines to define the thrust to be generated and tothe nozzles to define the position that the nozzles should assume.Typically, the current commands are represented by a vector {overscore(δ)} which includes a term defining the state to which each respectivecontrol effector is currently commanded.

[0027] Based upon the current control effector commands {overscore (δ)},the anticipated changes in the plurality of states of the aerodynamicvehicle are determined. In this regard, an aerodynamic vehicle that isin flight has a number of states {overscore (X)}, including the angle ofattack, the angle of side slip, the air speed, the vehicle attitude, thelift, the altitude and the like. In addition, the states of anaerodynamic vehicle that are considered by the control method may alsoinclude a plurality of engine parameters, such as temperature, pressure,total area and the like. As known to those skilled in the art, thestates of an aerodynamic vehicle may vary somewhat depending upon thetype and model of the aerodynamic vehicle, but are well defined for arespective type and model of aerodynamic vehicle.

[0028] In order to determine the anticipated changes in the system rateof change of the state vector {overscore (x)} of the aerodynamic vehiclebased upon the current commands {overscore (δ)}, a matrix$\lbrack \frac{\partial\overset{\overset{.}{\_}}{x}}{\partial\overset{\_}{\delta}} \rbrack$

[0029] may be defined that represents changes in the rate of change ofthe respective states (hereinafter termed the state rates) of theaerodynamic vehicle in response to changes in the plurality of controleffectors. See block 10 of FIG. 1. The matrix includes a plurality ofterms with each term representing the change in a respective state rateof the aerodynamic vehicle in response to the change of a respectivecontrol effector. As such, the matrix represents the manner in which theaerodynamic vehicle is anticipated to respond to changes in the controleffectors. Typically, the matrix is constructed to have a plurality ofrows and a plurality of columns. Each column generally includes aplurality of terms, each of which defines the anticipated change in arespective state rate of the aerodynamic vehicle in response to thechange in the same control effector. Thus, each column of the matrixrepresents the anticipated changes in the state rates of the aerodynamicvehicle due to a change of a respective control effector.

[0030] The matrix$\lbrack \frac{\partial\overset{\overset{.}{\_}}{x}}{\partial\overset{\_}{\delta}} \rbrack$

[0031] may be constructed by a variety of techniques. In one technique,the matrix is constructed as a result of numerical calculations. In thistechnique, the current states of the aerodynamic vehicle and the currentsettings of the control effectors are provided. Based upon the currentstates of the aerodynamic vehicle and the current settings of thecontrol effectors, the resulting forces and torques acting upon theaerodynamic vehicle are determined. By factoring in the mass and inertiaof the aerodynamic vehicle, the state rates may be determined.

[0032] In order to determine the resulting forces and torques actingupon the aerodynamic vehicle, the aerodynamic coefficients for thecurrent flight condition, as defined by the current states {overscore(x)} of the aerodynamic vehicle, are determined. As known to thoseskilled in the art, aerodynamic databases are available for mostaerodynamic vehicles that define the various aerodynamic coefficientsbased upon the current states of the aerodynamic vehicle. Theaerodynamic coefficients of an aerodynamic vehicle may vary based uponthe type and model of the aerodynamic vehicle, but typically includecoefficients such as lift, drag, pitching moment, side force, rollingmoment, yawing moment and the like. While the aerodynamic coefficientsmay vary based upon the type and model of the aerodynamic vehicle, theaerodynamic coefficients for a particular type and model of aerodynamicvehicle will be well defined and known to those skilled in the art.

[0033] The resulting forces and torques upon the aerodynamic vehicle canthen be determined based upon the aerodynamic coefficients by means offorce buildup equations, also known to those skilled in the art. In thisregard, the force buildup equations will also generally vary dependingupon the type and model of aerodynamic vehicle. However, for aparticular type and model of aerodynamic vehicle, the force buildupequations are well established and known to those skilled in the art. Inaddition to the aerodynamic coefficients, force buildup equationsgenerally take into account the current dynamic pressure as well as anumber of other parameters, such as the mass, inertia, span, referencearea and the like, which are well known to those skilled in the art. Thedynamic pressure is based upon the square of the velocity such that theforce buildup equations effectively take into account the current flightconditions.

[0034] The anticipated changes in the state rates of the aerodynamicvehicle are then determined based upon finite differences. In thisregard, one control effector is considered to have varied slightly, suchas 1% or less, from its current state and the process of determining theresulting forces and torques acting upon the aerodynamic vehicle isrepeated, albeit with the state of one control effector having beenvaried somewhat. The resulting change in the forces and torques actingupon the aerodynamic vehicle following the slight variation of onecontrol effector are then determined. By factoring out the mass andinertia of the aerodynamic vehicle from the force buildup equationsrepresentative of the changes in the forces and torques occasioned by aslight variation in one control effectors, the change in each state rateof the aerodynamic vehicle attributable to the change in the respectivecontrol effector may be determined, thereby defining one column in theresulting matrix$\lbrack \frac{\partial\overset{\overset{.}{\_}}{x}}{\partial\overset{\_}{\delta}} \rbrack.$

[0035] The foregoing process of slightly varying a respective controleffector and determining the resulting change in forces and torquesacting upon the aerodynamic vehicle and, correspondingly, the resultingchanges in the state rates of the aerodynamic vehicle is repeated foreach control effector in order to construct the entire matrix.

[0036] Alternatively, the matrix$\lbrack \frac{\partial\overset{\overset{.}{\_}}{x}}{\partial\overset{\_}{\delta}} \rbrack$

[0037] may be determined based upon an analytic calculation. Accordingto this alternative technique, a nonlinear multidimensional analyticcurve may be fit to each respective aerodynamic coefficient defined bythe aerodynamic database. In this regard, the aerodynamic databaseseparately defines each aerodynamic coefficient at each of a largenumber of different flight conditions, with a respective flightcondition defined by a respective system state vector {overscore (x)}and the current state of the control effectors. The nonlinearmultidimensional curves may be fit to respective aerodynamiccoefficients according to any of a variety of techniques. In oneembodiment, however, the nonlinear multidimensional curves are fit torespective aerodynamic coefficients. Since the aerodynamic coefficientsare now represented by analytic functions, the partial derivatives ofeach aerodynamic coefficient with respect to a change in a respectivecontrol effector may then be readily determined by hand or, morecommonly, by utilizing a commercially available program such asMathematica. By utilizing the nonlinear multidimensional polynomialcurve representing each aerodynamic coefficient, along with dynamicpressure, vehicle mass, inertia, span, reference area and otherparameters, the force buildup equations for the aerodynamic vehicle mayagain be constructed as known to those skilled in the art. The partialderivatives of each force with respect to each aerodynamic coefficientmay then be determined. By utilizing the chain rule and the partialderivatives of the aerodynamic coefficients with respect to changes inrespective control effectors and the partial derivatives of the forceswith respect to respective aerodynamic coefficients, the partialderivatives of the forces with respect to changes in respective controleffectors may be determined. By factoring out the mass and inertia ofthe aerodynamic vehicle, the partial derivatives of the forces withrespect to changes in respective control effectors can be translatedinto the partial derivatives of the state rates of the aerodynamicvehicle with respect to changes in each control effector. Thereafter,the matrix can be constructed as described above.

[0038] Regardless of the manner in which the matrix$\lbrack \frac{\partial\overset{\overset{.}{\_}}{x}}{\partial\overset{\_}{\delta}} \rbrack$

[0039] is to be constructed, the matrix is preferably determined in realtime based upon the current flight conditions including the dynamicpressure and the current control effector commands {overscore (δ)} ofthe aerodynamic vehicle. Following construction of the matrix, theanticipated change in each state rate of the aerodynamic vehicle isdetermined by the vector multiplication of the vector {overscore (δ)}representing the current commands and the matrix. In particular, the dotproduct of the vector representing the current commands and the matrixis determined.

[0040] By taking into account the current flight conditions including,for example, the dynamic pressure and, in turn, the velocity of theaerodynamic vehicle during the construction of the matrix, theanticipated change in the plurality of state rates is based not onlyupon the current commanded state of the control effectors, but also thecurrent flight conditions. In this regard, the matrix is constructedsuch that the anticipated change in each state rate is dominated atthose phases of flight, such as vertical takeoff and landing, in whichthe aerodynamic vehicle has low or no velocity by the thrust variationsand the nozzle vectoring with little if any, contribution by theaerodynamic surfaces. As the velocity increases, the contributionprovided by the aerodynamic surfaces to the anticipated change in eachstate rate correspondingly increases while the contribution provided bythrust variations and nozzle vectoring remains unchanged until thecontributions provided by the aerodynamic surfaces are of sufficientmagnitude to control the anticipated changes in each state rate athigher velocities without the aid of propulsive devices, such as thrustvariations and nozzle vectoring. The increasing dynamic pressure haslittle affect on the amount of control authority generated by propulsivedevices. So, as dynamic pressure increases, the amount of augmenationrequired by the use of the propulsive devices decreases until theaerodynamic surfaces provide all the required authority and thepropulsive devices can be turned off to conserve fuel or used toincrease airspeed. Generally, aerodynamic surfaces are a much moreefficient way to control the air vehicle when compared to propulsivedevices.

[0041] The desired change {overscore (x)}_(com) in the respective staterates of the aerodynamic vehicle is also provided, such as by pilotinput, and is stored by a conventional sample and hold circuit 11. Thisdesired change {overscore (x)}_(com) in the respective state rates ofthe aerodynamic vehicle may represent a change in the state rates ofselected states of the aerodynamic vehicle or all of the states of theaerodynamic vehicle, typically depending upon the pilot input. In orderto determine the manner in which the control effectors must becontrolled in order to affect the desired change {overscore (x)}_(com)in the respective state rates of the aerodynamic vehicle, the differencebetween the anticipated and desired changes in the state rates of theaerodynamic vehicle is determined. Since the desired change {overscore(x)}_(com) in the respective state rates of the aerodynamic vehicle isalso typically represented by a vector, the vector difference betweenthe dot product representing the anticipated change in state rates ofthe aerodynamic vehicle and the vector representing the desired changesin the state rates is obtained as shown in block 12 of FIG. 1.

[0042] According to one advantageous aspect of the present invention,the difference between the anticipated and desired changes in the staterates of the aerodynamic vehicle may be weighted based upon a predefinedcriteria. One predefined criteria defines the relative importance of therespective states of the aerodynamic vehicle. Thus, the differencesbetween the anticipated and desired changes in the state rates of theaerodynamic vehicle, typically represented as a vector difference, canbe weighted so as to affect changes in some states of the aerodynamicvehicle more rapidly than other states due to the relative importance ofthe states for which changes are more rapidly affected. As such, arespective weight {overscore (w)} may be assigned to the state of theaerodynamic vehicle, such as during system configuration or the like.

[0043] Another predetermined criteria is a predefined penalty {overscore(p)} that may serve to place lesser or greater emphasis on outliervalues. In this regard, the effect of the predefined penalty will varybased upon the magnitude of the difference between the anticipated anddesired changes in the respective state rate of the aerodynamic vehicle,with relative large differences being considered outliers. For example,small penalties may be assigned to the outliers in those systems thatare designed to factor the impact of the outliers into the controlprocess, while large penalties may be assigned to outliers in thosesystems that desire to deemphasize the contributions of outliers sincethey may be attributable to an error. By way of example, the controlmethod desirably maintains the total area required by each engine. Inthis regard, for a respective engine providing a certain level ofthrust, the effective outlet area that the engine sees must remainconstant as the nozzles are opened, closed and repositioned.

[0044] In order to affect the weighting, the vector operator

(designated 14 in FIG. 1) is defined as follows:

({overscore (v)},{overscore (w)},{overscore (p)})_(i) =w _(i) sgn(v_(i))∥v _(i)∥^(p) ^(_(i)) ⁻¹

[0045] wherein i represents a respective state of the aerodynamicvehicle, w_(i) is the weight assigned to each state of the aerodynamicvehicle, p_(i) is the predefined penalty assigned to each state of theaerodynamic vehicle and v_(i) is the difference between the anticipatedand desired changes in each state rate of the aerodynamic vehicle. Bothw_(i) and p_(i) are defined to be greater than or equal to 0. Bymultiplying the vector difference between the anticipated and desiredchanges in the state rates of the aerodynamic vehicle and the vectoroperator

as shown in block 14, the weighted differences between the anticipatedand desired changes in the state rates of the aerodynamic vehicle areobtained.

[0046] These weighted differences between the anticipated and desiredchanges in the state rates of the aerodynamic vehicle are then convertedto the corresponding changes in the control effectors to bring about thedesired changes {overscore (x)}_(com) in the state rates. In theillustrated embodiment, the weighted differences are multiplied by thetranspose$\lbrack \frac{\partial\overset{\overset{.}{\_}}{x}}{\partial\overset{\_}{\delta}} \rbrack^{T}$

[0047] of the matrix representing the changes in the state rates of theaerodynamic vehicle in response to the changes in the plurality ofcontrol effectors as shown in block 16 of FIG. 1. In other words, thedot product of the weighted vector difference and the transpose of thematrix representing changes in the state rates of the aerodynamicvehicle in response to changes in the plurality of control effectors isdetermined. As such, the rate of changes {overscore (δ)} of the controleffectors required to affect the desired changes in the state rates ofthe aerodynamic vehicle subject to the anticipated changes in the staterates of the aerodynamic vehicle based upon the current commanded stateof each control effector is determined. Since each term of the vectordifference between the anticipated and desired changes in the staterates of the aerodynamic vehicle has been weighted, the resultingcommands to the control effectors to affect the desired change in thestate rates of the aerodynamic vehicle are computed based upon thepredetermined criteria, such as the relative importance of therespective states of the aerodynamic vehicle and/or the weighting to begiven to any outlier measurements. By multiplying the weighteddifferences by the transpose of the matrix representing changes in thestate rates of the aerodynamic vehicle in response to changes in thecontrol effectors, the control method employs a gradient descenttechnique so as to cause the control effectors that will have thegreatest impact upon effecting the desired change to be adjusted morethan the control effectors that would have less impact upon effectingthe desired change, thereby improving the efficiency of the controlscheme by using all available effectors in a coordinated fashion.

[0048] The rate of changes {overscore (δ)} of the control effectorsrequired to affect the desired changes in the state rates of theaerodynamic vehicle may also be weighted by a gain matrix as shown byblock 17 based upon the relative or perceived importance of therespective control effectors. The gain matrix K_(ij) is a diagonal,positive, semi-definite matrix with one term of the gain matrixassociated with the rate of change of each respective control effector.Typically the values of the gain matrix are selected in advance withvalues larger than one serving to increase the rate of change of therespective control effector and values less than one serving to decreasethe rate of change of the respective control effector.

[0049] Since control effectors are typically subject to at least somelimitations, such as limitations in the predefined range of the controleffector and limitations in the permissible rate of change of thecontrol effector, the method and computer program product of oneadvantageous aspect of the present invention limit the permissiblechange of each control effector that has these predefined limitationssuch that the resulting commands issued to the control effectors do notattempt to exceed the limitations of the control effectors. Differentlimitations may be imposed upon different control effectors. Forexample, the control signals otherwise provided to the control effectorsmay be limited, such as by a vector limiter as shown in block 18 of FIG.1, to prevent the respective control effector from being commanded tochange at a rate that exceeds a predefined limit. In this regard, upperand/or lower limits may be predefined such that the permissible rate ofchange of the respective control effector must remain within theacceptable range bounded by the limit(s). However, in instances in whichthe aerodynamic vehicle includes a failure detection system, the upperand lower limits may be set to the position of the effector or effectorswhich are indicated as failed to maintain available performance in thisdegraded mode of operation.

[0050] In order to convert the rates of change {overscore (δ)} of thecontrol effectors that have been determined to create the desired changein the state rates and, in turn, the state of the aerodynamic vehicleinto control effector commands, the rates of change are integrated asrepresented by block 20 of FIG. 1. In this regard, the rates of changeare integrated by employing a local feedback loop in which a time delay22 and a limiter 24 are located in the feedforward path. The limiterserves to maintain each control effector within a predefined range. Forexample, the position of a nozzle or control surface may be limited soas to remain within a predefined range of positions, also typicallydefined by predefined upper and/or lower limits.

[0051] Once the desired changes in the control effectors have beenappropriately limited so as to prevent any control effector from beingcommanded to exceed its predefined limitations, the changes in eachcontrol effector that have been determined to affect the desired changein the state rates of the aerodynamic vehicle are issued as commands toeach of the control effectors and, in the illustrated embodiment, arestored by the zero order hold 26. As such, the desired change in thestate rates and, in turn, the desired change in the time rate of changeof the system state vector of the aerodynamic vehicle will be affected.

[0052] By weighting the differences between the anticipated and desiredchanges in the state rates of the aerodynamic vehicle, the method of thepresent invention effectively affects the desired change in theplurality of states of the aerodynamic vehicle in a manner whichminimizes the associated costs, as defined by the weighting. In thisregard, the cost of the change in the plurality of states of theaerodynamic vehicle is defined as follows:${{cost}( {\overset{\_}{\delta},\overset{\_}{w},\overset{\_}{p}} )} = {( {\sum\limits_{i = 1}^{n}\quad {w_{i}\frac{1}{p_{i}}{{sgn}( {{\lbrack \frac{\partial\overset{\overset{.}{\_}}{x}}{\partial\overset{\_}{\delta}} \rbrack \overset{\_}{\delta}} - {\overset{\overset{.}{\_}}{x}}_{com}} )}{{{\lbrack \frac{\partial\overset{\overset{.}{\_}}{x}}{\partial\overset{\_}{\delta}} \rbrack \overset{\_}{\delta}} - {\overset{\overset{.}{\_}}{x}}_{com}}}^{p_{i}}}} ).}$

[0053] As described above, this cost is minimized even in instances inwhich one or more of the control effectors failed or are otherwisedefective or frozen in position by design. In this regard, the controlmethod is robust to failures of one or more control effectors since theremaining control effectors are forced or commanded in the direction tobring about the desired change while minimizing the resulting costs.Since the continued use of the failed control effectors will come at alarge cost due to the predefined penalty p_(i) assigned to outliers, theminimization of the cost will cause the other functional controleffectors to be recruited and repositioned to affect the desired change.

[0054] By minimizing the resulting cost of affecting the desired changesin the state rates of the aerodynamic vehicle, the control method of thepresent invention affects the desired changes in an efficient manner.See copending U.S. patent application Ser. Nos. 09/967,403 and09/967,446 for further discussion of the cost function. The entirecontents of each of these applications is incorporated herein byreference.

[0055] Based upon the cost function, the affect of the predefinedpenalty p_(i) that permits greater or lesser emphasis to be placed uponoutliers, i.e., large differences between the anticipated and desiredchanges in the state rates, can be illustrated. In this regard, FIGS. 2and 3 are two different graphical illustrations of the same curvesrepresenting the relationship between the cost and difference v betweenthe anticipated and desired change in a respective state rate of anaerodynamic vehicle. As indicated, larger values of p, i.e., p>2, imposegreater penalties upon outliers, thereby increasing the overall cost.Conversely, smaller values of p, i.e., 1<p<2, permit outliers tocontinue to contribute to the cost, thereby decreasing the cost. Thus,the control of the control effectors may be tailored by a systemdesigner or the like based upon the manner in which outliers which maybe representative of an error or failure in the system are to be treatedby either being excluded from the control system or by continuing to beincluded, either completely or in some partial degree. In addition, thecontrol of the control effectors may be further tailored as describedabove by establishing another weighting w based upon the relativeimportance of the respective states of the aerodynamic vehicle.

[0056] Furthermore, both the continuous and discrete modes of thecontrol method converge. Proof of this convergence is provided bycopending U.S. patent application Ser. Nos. 09/967,403 and 09/967,446.Moreover, the control method is capable of quickly determining and thenrepeatedly redetermining the command to be issued to the controleffector so as to insure that vehicle stability is maintained. While thecontrol method was designed to be rapid, embodiments of the controlmethod may utilize single precision floating point numericalrepresentations of the various quantities in order to obtain accuratecommands while further increasing the computational throughput.

[0057] As indicated above, the method of controlling the plurality ofcontrol effectors of an aerodynamic vehicle may be embodied by acomputer program product that directs the operation of a flight controlcomputer or the like to issue the commands to the plurality of controleffectors in order to affect the desired changes. In this regard, thecomputer program product includes a computer-readable storage medium,such as the non-volatile storage medium, and computer-readable programcode portions, such as a series of computer instructions, embodied inthe computer-readable storage medium. Typically, the computer program isstored by a memory device and executed by an associated processing unit,such as the flight control computer or the like.

[0058] In this regard, FIG. 1 is a block diagram, flowchart and controlflow illustration of methods and program products according to theinvention. It will be understood that each block or step of the blockdiagram, flowchart and control flow illustrations, and combinations ofblocks in the block diagram, flowchart and control flow illustrations,can be implemented by computer program instructions. These computerprogram instructions may be loaded onto a computer or other programmableapparatus to produce a machine, such that the instructions which executeon the computer or other programmable apparatus create means forimplementing the functions specified in the block diagram, flowchart orcontrol flow block(s) or step(s). These computer program instructionsmay also be stored in a computer-readable memory that can direct acomputer or other programmable apparatus to function in a particularmanner, such that the instructions stored in the computer-readablememory produce an article of manufacture including instruction meanswhich implement the function specified in the block diagram, flowchartor control flow block(s) or step(s). The computer program instructionsmay also be loaded onto a computer or other programmable apparatus tocause a series of operational steps to be performed on the computer orother programmable apparatus to produce a computer implemented processsuch that the instructions which execute on the computer or otherprogrammable apparatus provide steps for implementing the functionsspecified in the block diagram, flowchart or control flow block(s) orstep(s).

[0059] Accordingly, blocks or steps of the block diagram, flowchart orcontrol flow illustrations support combinations of means for performingthe specified functions, combinations of steps for performing thespecified functions and program instruction means for performing thespecified functions. It will also be understood that each block or stepof the block diagram, flowchart or control flow illustrations, andcombinations of blocks or steps in the block diagram, flowchart orcontrol flow illustrations, can be implemented by special purposehardware-based computer systems which perform the specified functions orsteps, or combinations of special purpose hardware and computerinstructions.

[0060] Many modifications and other embodiments of the invention willcome to mind to one skilled in the art to which this invention pertainshaving the benefit of the teachings presented in the foregoingdescriptions and the associated drawings. Therefore, it is to beunderstood that the invention is not to be limited to the specificembodiments disclosed and that modifications and other embodiments areintended to be included within the scope of the appended claims.Although specific terms are employed herein, they are used in a genericand descriptive sense only and not for purposes of limitation.

That which is claimed:
 1. An integrated method of controlling aplurality of control effectors of an aerodynamic vehicle having aplurality of states, the method comprising: determining a currentcommanded state of the plurality of control effectors including thecurrent commanded states of nozzle vectoring and at least oneaerodynamic surface; determining differences between anticipated changesin the plurality of states of the aerodynamic vehicle based upon thecurrent commanded state of the plurality of control effectors anddesired changes in the plurality of states of the aerodynamic vehicle;and controlling the plurality of control effectors at least partiallybased upon the differences in order to implement at least a portion ofthe desired changes in the plurality of states of the aerodynamicvehicle.
 2. An integrated method according to claim 1 whereindetermining the differences between the anticipated and desired changesin the plurality of states of the aerodynamic vehicle comprisesdetermining the anticipated changes in the plurality of states basedupon the current commanded state of each control effector and currentflight conditions.
 3. An integrated method according to claim 1 whereincontrolling the plurality of control effectors comprises adjusting acontrol effector that effects a greater portion of the desired changemore than a control effector that effects a smaller portion of thedesired change.
 4. An integrated method according to claim 1 furthercomprising limiting the permissible change of at least one of thecontrol effectors, wherein controlling the plurality of controleffectors comprises controlling the plurality of control effectors basedupon the weighted differences subject to limitations in the permissiblechanges of at least one of the control effectors in order to implementat least a portion of the desired change in the plurality of states ofthe aerodynamic vehicle without exceeding the permissible changes of atleast one of the control effectors.
 5. An integrated method according toclaim 4 wherein limiting the permissible changes of at least one of thecontrol effectors comprises limiting the permissible rate of change ofat least one of the control effectors.
 6. An integrated method accordingto claim 4 wherein limiting the permissible changes of at least one ofthe control effectors comprises limiting at least one of the controleffectors to within a predefined range.
 7. An integrated methodaccording to claim 1 further comprising weighting the differencesbetween the anticipated and desired changes based upon a predeterminedcriteria, and wherein controlling the plurality of control effectors isat least partially based upon the weighted differences.
 8. An integratedmethod according to claim 7 wherein weighting the differences comprisesweighting the differences based upon the relative importance of therespective states of the aerodynamic vehicle.
 9. An integrated methodaccording to claim 7 wherein weighting the differences comprisesweighting the differences based upon a predefined penalty having aneffect that varies based upon the magnitude of a respective difference.10. An integrated method according to claim 1 wherein determining thedifferences between the anticipated and desired changes in the pluralityof states of the aerodynamic vehicle comprises: determining a first dotproduct of a vector representing the current commanded state of eachcontrol effectors and a matrix representing changes in the plurality ofstate rates of the aerodynamic vehicle in response to changes in theplurality of control effector, wherein the matrix is comprised of aplurality of terms, each term representing the anticipated change in arespective state rate of the aerodynamic vehicle in response to thechange of a respective control effector; and obtaining a vectordifference between the first dot product and a vector representing thedesired change in the plurality of states of the aerodynamic vehicle.11. An integrated method according to claim 10 further comprisingconstructing the matrix to represent changes in the state ratesassociated with lift, attitude and a plurality of engine parameters ofthe aerodynamic vehicle in response to changes in the plurality ofcontrol effectors.
 12. An integrated method according to claim 10further comprising determining a second dot product of the weightedvector difference and a transpose of the matrix representing changes inthe plurality of state rates of the aerodynamic vehicle in response tochanges in the plurality of control effectors, and wherein controllingthe plurality of control effectors is at least partially based upon thesecond dot product.
 13. An integrated method according to claim 12further comprising weighting the second dot product based upon therelative importance of the respective control effectors such that theplurality of control effectors are controlled based, at least partially,upon the weighted second dot product.
 14. An integrated method ofcontrolling a plurality of control effectors of an aerodynamic vehiclehaving a plurality of states, the method comprising: determining acurrent commanded state of a plurality of control effectors includingthe current commanded state of at least one aerodynamic surface and atleast one control effector selected from the group consisting of thrustvariations and nozzle vectoring; determining differences betweenanticipated changes in the plurality of states of the aerodynamicvehicle based upon the current commanded state of the plurality ofcontrol effectors and desired changes in the plurality of states of theaerodynamic vehicle; weighting the differences based upon at least oneof the relative importance of the respective states of the aerodynamicvehicle and a predefined penalty having an effect that varies based uponthe magnitude of a respective difference; and controlling the pluralityof control effectors at least partially based upon the weighteddifferences in order to implement at least a portion of the desiredchanges in the plurality of states of the aerodynamic vehicle.
 15. Anintegrated method according to claim 14 wherein determining thedifferences between the anticipated and desired changes in the pluralityof states of the aerodynamic vehicle comprises determining theanticipated changes in the plurality of states based upon the currentcommanded state of each control effector and current flight conditions.16. An integrated method according to claim 14 wherein controlling theplurality of control effectors comprises adjusting a control effectorthat effects a greater portion of the desired change more than a controleffector that effects a smaller portion of the desired change.
 17. Anintegrated method according to claim 14 further comprising limiting thepermissible change of at least one of the control effectors, whereincontrolling the plurality of control effectors comprises controlling theplurality of control effectors based upon the weighted differencessubject to limitations in the permissible changes of at least one of thecontrol effectors in order to implement at least a portion of thedesired change in the plurality of states of the aerodynamic vehiclewithout exceeding the permissible changes of at least one of the controleffectors.
 18. An integrated method according to claim 17 whereinlimiting the permissible changes of at least one of the controleffectors comprises limiting the permissible rate of change of at leastone of the control effectors.
 19. An integrated method according toclaim 17 wherein limiting the permissible changes of at least one of thecontrol effectors comprises limiting at least one of the controleffectors to within a predefined range.
 20. An integrated methodaccording to claim 14 wherein determining the differences between theanticipated and desired changes in the plurality of states of theaerodynamic vehicle comprises: determining a first dot product of avector representing the current commanded state of each controleffectors and a matrix representing changes in the plurality of staterates of the aerodynamic vehicle in response to changes in the pluralityof control effector, wherein the matrix is comprised of a plurality ofterms, each term representing the anticipated change in a respectivestate rate of the aerodynamic vehicle in response to the change of arespective control effector; and obtaining a vector difference betweenthe first dot product and a vector representing the desired change inthe plurality of states of the aerodynamic vehicle, and whereinweighting the differences comprises weighting the vector difference. 21.An integrated method according to claim 20 further comprisingconstructing the matrix to represent changes in the state ratesassociated with lift, attitude and a plurality of engine parameters ofthe aerodynamic vehicle in response to changes in the plurality ofcontrol effectors.
 22. An integrated method according to claim 20further comprising determining a second dot product of the weightedvector difference and a transpose of the matrix representing changes inthe plurality of state rates of the aerodynamic vehicle in response tochanges in the plurality of control effectors, and wherein controllingthe plurality of control effectors is at least partially based upon thesecond dot product.
 23. An integrated method according to claim 20further comprising weighting the second dot product based upon therelative importance of the respective control effectors such that theplurality of control effectors are controlled based, at least partially,upon the weighted second dot product.
 24. An integrated method ofcontrolling a plurality of control effectors of an aerodynamic vehiclehaving a plurality of states, the method comprising: determining acurrent commanded state of a plurality of control effectors includingthe current commanded state of at least one aerodynamic surface and atleast one control effector selected from the group consisting of thrustvariations and nozzle vectoring; determining differences betweenanticipated changes in the plurality of states of the aerodynamicvehicle based upon the current commanded state of each of the pluralityof control effectors and desired changes in the plurality of states ofthe aerodynamic vehicle; limiting the permissible change of at least oneof the control effectors; and controlling the plurality of controleffectors at least partially based upon differences between theanticipated and desired changes in the plurality of states of theaerodynamic vehicle subject to limitations in the permissible changes ofat least one of the control effectors in order to implement at least aportion of the desired change in the plurality of states of theaerodynamic vehicle without exceeding the permissible changes of atleast one of the control effectors.
 25. An integrated method accordingto claim 24 wherein determining the differences between the anticipatedand desired changes in the plurality of states of the aerodynamicvehicle comprises determining the anticipated changes in the pluralityof states based upon the current commanded state of each controleffector and current flight conditions.
 26. An integrated methodaccording to claim 24 wherein controlling the plurality of controleffectors comprises adjusting a control effector that effects a greaterportion of the desired change more than a control effector that effectsa smaller portion of the desired change.
 27. An integrated methodaccording to claim 24 wherein limiting the permissible changes of atleast one of the control effectors comprises limiting the permissiblerate of change of at least one of the control effectors.
 28. Anintegrated method according to claim 24 wherein limiting the permissiblechanges of at least one of the control effectors comprises limiting atleast one of the control effectors to within a predefined range.
 29. Anintegrated method according to claim 24 further comprising weighting thedifferences between the anticipated and desired changes based upon apredetermined criteria, and wherein controlling the plurality of controleffectors is at least partially based upon the weighted differences. 30.An integrated method according to claim 29 wherein weighting thedifferences comprises weighting the differences based upon the relativeimportance of the respective states of the aerodynamic vehicle.
 31. Anintegrated method according to claim 29 wherein weighting thedifferences comprises weighting the differences based upon a predefinedpenalty having an effect that varies based upon the magnitude of arespective difference.
 32. An integrated method according to claim 24wherein determining the differences between the anticipated and desiredchanges in the plurality of states of the aerodynamic vehicle comprises:determining a first dot product of a vector representing the currentcommanded state of each of the plurality of control effectors and amatrix representing changes in the plurality of state rates of theaerodynamic vehicle in response to changes in the plurality of controleffectors, wherein the matrix is comprised of a plurality of terms, eachterm representing the anticipated change in a respective state rate ofthe aerodynamic vehicle in response to the change of a respectivecontrol effector; and obtaining a vector difference between the firstdot product and a vector representing the desired change in theplurality of states of the aerodynamic vehicle.
 33. An integrated methodaccording to claim 32 further comprising constructing the matrix torepresent changes in the state rates associated with lift, attitude anda plurality of engine parameters of the aerodynamic vehicle in responseto changes in the plurality of control effectors.
 34. An integratedmethod according to claim 32 further comprising determining a second dotproduct of a representation of the vector difference and a transpose ofthe matrix representing changes in the plurality of state rates of theaerodynamic vehicle in response to changes in the plurality of controleffectors, and wherein controlling the plurality of control effectors isat least partially based upon the second dot product.
 35. An integratedmethod according to claim 34 further comprising weighting the second dotproduct based upon the relative importance of the respective controleffectors such that the plurality of control effectors are controlledbased, at least partially, upon the weighted second dot product.
 36. Acomputer program product for controlling a plurality of controleffectors of an aerodynamic vehicle having a plurality of states, thecomputer program product comprising a computer-readable storage mediumhaving computer-readable program code embodied in said medium, thecomputer-readable program code comprising: a first executable portionadapted to determine a current commanded state of the plurality ofcontrol effectors including the current commanded states of nozzlevectoring and at least one aerodynamic surface; a second executableportion adapted to determine differences between anticipated changes inthe plurality of states of the aerodynamic vehicle based upon thecurrent commanded state of the plurality of control effectors anddesired changes in the plurality of states of the aerodynamic vehicle;and a third executable portion adapted to control the plurality ofcontrol effectors at least partially based upon the differences in orderto implement at least a portion of the desired changes in the pluralityof states of the aerodynamic vehicle.
 37. A computer program productaccording to claim 36 wherein said second executable portion is adaptedto determine the anticipated changes in the plurality of states basedupon the current commanded state of each control effector and currentflight conditions.
 38. A computer program product according to claim 36wherein said third executable portion is adapted to adjust a controleffector that effects a greater portion of the desired change more thana control effector that effects a smaller portion of the desired change.39. A computer program product according to claim 36 further comprisinga fourth executable portion adapted to limit the permissible change ofat least one of the control effectors, wherein said third executableportion is adapted to control the plurality of control effectors basedupon the weighted differences subject to limitations in the permissiblechanges of at least one of the control effectors in order to implementat least a portion of the desired change in the plurality of states ofthe aerodynamic vehicle without exceeding the permissible changes of atleast one of the control effectors.
 40. A computer program productaccording to claim 39 wherein said fourth executable portion is adaptedto limit the permissible rate of change of at least one of the controleffectors.
 41. A computer program product according to claim 39 whereinsaid fourth executable portion is adapted to limit at least one of thecontrol effectors to within a predefined range.
 42. A computer programproduct according to claim 36 further comprising a fifth executableportion adapted to weight the differences between the anticipated anddesired changes based upon a predetermined criteria, and wherein saidthird executable portion is adapted to control the plurality of controleffectors at least partially based upon the weighted differences.
 43. Acomputer program product according to claim 42 wherein said fifthexecutable portion is adapted to weight the differences based upon therelative importance of the respective states of the aerodynamic vehicle.44. A computer program product according to claim 42 wherein said fifthexecutable portion is adapted to weight the differences based upon apredefined penalty having an effect that varies based upon the magnitudeof a respective difference.
 45. A computer program product according toclaim 36 wherein said second executable portion is adapted to determinea first dot product of a vector representing the current commanded stateof each control effectors and a matrix representing changes in theplurality of state rates of the aerodynamic vehicle in response tochanges in the plurality of control effector, wherein the matrix iscomprised of a plurality of terms, each term representing theanticipated change in a respective state rate of the aerodynamic vehiclein response to the change of a respective control effector, and whereinsaid second executable portion is also adapted to obtain a vectordifference between the first dot product and a vector representing thedesired change in the plurality of states of the aerodynamic vehicle.46. A computer program product according to claim 45 further comprisinga sixth executable portion adapted to construct the matrix to representchanges in the state rates associated with lift, attitude and aplurality of engine parameters of the aerodynamic vehicle in response tochanges in the plurality of control effectors.
 47. A computer programproduct according to claim 45 further comprising a seventh executableportion adapted to determine a second dot product of the weighted vectordifference and a transpose of the matrix representing changes in theplurality of state rates of the aerodynamic vehicle in response tochanges in the plurality of control effectors, and wherein said thirdexecutable portion is adapted to control the plurality of controleffectors at least partially based upon the second dot product.
 48. Acomputer program product according to claim 47 further comprising aneighth executable portion adapted to weight the second dot product basedupon the relative importance of the respective control effectors suchthat the plurality of control effectors are controlled based, at leastpartially, upon the weighted second dot product.